Image sensors are widely used in imaging devices, such as digital cameras, medical imaging equipment, thermal imaging devices, radar, sonar, and other electronic devices. Such imaging devices that include the image sensors may be associated with digital Correlated Double Sampling (CDS) processing. The CDS processing may include a noise component and a true signal component. The noise component may be referred to as P-phase data. The true signal component may be referred to as D-phase data. The difference between the P-phase data and the D-phase data may be used to remove noise, such as an internal thermal noise (kTC noise), associated with an image or a sequence of images to be captured by use of an image sensor of an imaging device. However, in imaging devices that use a global shutter, the CDS process requires the noise component, such as the P-phase data, to be stored before the true signal component, such as the D-phase data, received from the image sensor. The global shutter may refer to a shutter mode that controls incoming light to all light-sensitive elements of an imaging device simultaneously. Thus, in the imaging devices that use the global shutter, every pixel may be exposed simultaneously at the same instant in time. In order to save memory or storage space of the imaging device, it may be desirable to compress the noise component, such as the P-phase data. The compression of the P-phase data requires that the kTC noise should remain constant while there is a reduction of the additional noise incurred due to P-phase data compression.
Conventional compression methods for low-complexity compression may include differential pulse code modulation (DPCM). DPCM may be effective for image compression, where the captured image has adjacent pixel intensity values that are highly similar to each other. However, for data that exhibit noise-like characteristics, such as the P-phase data, the DPCM based compression method may not be effective for compression.
Further limitations and disadvantages of conventional and traditional approaches will become apparent to one of skill in the art, through comparison of described systems with some aspects of the present disclosure, as set forth in the remainder of the present application and with reference to the drawings.